Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 3, 2015
Previous Article Next Article

Microsolvation of 2-azetidinone: a model for the peptide group–water interactions

Author affiliations

Abstract

2-Azetidinone–water clusters can be considered as appropriate models for investigating the interaction of the peptide functional group with water. The rotational spectra of 2-azetidinone–(H2O)n (n = 1, 2) complexes have been studied in the 6–18 GHz frequency range using a molecular beam Fourier transform microwave spectrometer. Two different isomers have been observed for the 1 : 1 adduct. The most stable (1 : 1a) is stabilized by two hydrogen bonds O–H⋯O[double bond, length as m-dash]C and N–H⋯O with water closing a ring with the peptide group. For the other conformer (1 : 1b), water is placed on the other side of the carbonyl group stabilized by O–H⋯O[double bond, length as m-dash]C and C–H⋯O hydrogen bonds. In 2-azetidinone–(H2O)2 the water molecules close a ring with the peptide group forming three different hydrogen bonds: O–H⋯O[double bond, length as m-dash]C, O–H⋯O and N–H⋯O. The spectra of the parent and several isotopologues of each cluster have been investigated in order to determine their structures. The hydrogen bond geometries show that the dominant interaction is the O–H⋯O[double bond, length as m-dash]C hydrogen bond, in good agreement with the observed preference of water to interact with this group in proteins. A comparison between the geometries of the different observed adducts shows clearly how cooperative hydrogen bonding plays an important role in the stabilization of these complexes. No detectable structural changes have been observed for 2-azetidinone upon hydration with one water molecule.

Graphical abstract: Microsolvation of 2-azetidinone: a model for the peptide group–water interactions

Back to tab navigation

Supplementary files

Article information


Submitted
09 Oct 2014
Accepted
26 Nov 2014
First published
05 Dec 2014

Phys. Chem. Chem. Phys., 2015,17, 2054-2066
Article type
Paper

Microsolvation of 2-azetidinone: a model for the peptide group–water interactions

J. C. López, R. Sánchez, S. Blanco and J. L. Alonso, Phys. Chem. Chem. Phys., 2015, 17, 2054
DOI: 10.1039/C4CP04577G

Social activity

Search articles by author

Spotlight

Advertisements